Baffles in a reactor

I know the use of baffles in a shell and tube heat exchanger will guide the shell-side fluid as it navigates through the shell, but I saw baffles are also used in CSTRs to help with mixing.

This is clearly illustrated with the diagram
where one can see that the baffle is directing the shell fluid up and down, increasing the time it spends inside the exchanger, thus absorbs more heat from the tube side fluid, hence heat exchange. Very useful indeed.

Staff: Mentor

The ideal CSTR model assumes that the fluid in the reactor is perfectly mixed, and that there are no concentration gradients inside the reactor. However, in a real-world stirred tank reactor, you won't have perfect mixing and there will be concentration gradients present. The baffles contribute additional disturbance to the flow created by the mixer, and provide more effective mixing. So, including the baffles brings you closer to the ideal of perfect mixing.

Ever stirred a cup of tea or coffee and had the entire mass of fluid start rotating in the cup? As soon as it happens there is not much turbulence right? You can take your spoon out and watch it continue to spin for some time.
Imagine having baffles on the inside of your cup, how would that change the mixing?